package cn.jiyun.mapper;

import cn.jiyun.pojo.User;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.apache.ibatis.annotations.Select;

import java.util.List;
import java.util.Map;

/**
 * @author Fay
 * @date 2022/6/22&11:04
 */
public interface UserMapper extends BaseMapper<User> {
    @Select("select age,count(*) total from tb_user GROUP BY age")
    public List<Map> selectCountGroupByAge();
}
